Flow-control device

ABSTRACT

The invention concerns a float-controlled flow-control devie for the outlet from a sewage system, especially a rain basin. The bearings for the pivots (7 &amp; 8) that the float arm (4) and the shutter (2) rotate on are mounted on a displaceable structure (3). This makes it possible to vary the outflow volume to be controlled even when the device is in operation, and hence to control it remotely as well.

The invention concerns a flow-control device for the outlet from asewage system, especially a rain basin.

A flow-control device in the art is known from German OS No. 3 007 035.

The bearings for the pivots that the float arm and the flow-controlshutter rotate on are secured to the wall of the basin at prescribeddistance from the axis of the outlet. The drawback of this known deviceis that it is impossible to vary the distance (from the pivots to theoutlet) and hence the outflow curve when the device is in operation.

There exist, however, large drainage systems with a large number of rainbasins that, due to the large size of the catchment area, are subjectedto irregularly distributed precipitation. It would accordingly bedesirable in relation to protection against flooding to be able towithdraw more effluent from basins in the section of the catchment areawith more precipitation and less from those where the precipitation wasless or non-existent, so that the maximum access to the treatment plantcould be optimally exploited. This is impossible with the knownflow-control device.

Another drawback is that the volume of effluent traveling through theflow-control device cannot be adjusted to the expansion stage of thesewer network. Furthermore, the known flow-control device cannot beremotely operated.

The object of the invention is to improve a flow-control device of theknown type to the extent that the setting of the shutter can be adjustedeven during operation.

This object is attained by means of the characteristics of the body ofclaim 1.

The position of the moving structure can accordingly be varied manuallyor by means of a servomotor through the intermediary of a shaft or rod.

This results in a number of advantages. An optimum outflow can be set inan extensive sewage system with several basins as a function of theparticular operating state of each basin (with, that is, some of themfull, others partly full, and others empty). If it is desirable toadjust the outflow remotely instead of manually where electricity isavailable, the level of water in the basin can be displayed as afunction of the angle of one of the pivots and hence of the height ofthe float by means of an electric contact on the pivot. Thus, anadditional water-level meter will be unnecessary.

The outflow volume itself can also be displayed as a function of theposition of the moving structure by means of an electric contact mountedon the wall of the basin for instance.

The advantage of this solution over controls that are operated only withexternal power is that the actual control process is not interruptedduring power failure or other malfunctions in the electric circuitry.

If the device gets clogged, the moving structure can be raised toincrease the cross-section of the outlet while the obstruction isremoved. It will accordingly be unnecessary to empty the basin inemergencies.

The outflow volume that is to be controlled can be adapted to theexpansion stage of the sewer network.

An embodiment of the invention will now be specified with references toFIGS. 1 through 3, wherein

FIG. 1 is a front view of a device in accordance with the invention,

FIG. 2 is a section along the line A--A in FIG. 1, and

FIG. 3 is a section along the line B--B in FIG. 1.

As will be evident from FIGS. 1 and 2, the device in accordance with theinvention consists essentially of an outlet 1, of a shutter 2 thatrotates on a pivot 7, of a moving structure 3, of a float 5 mounted on afloat arm 4 that rotates on a pivot 8, and of a transmission 6 betweenfloat 5 and shutter 2.

The view in FIG. 1 illustrates the device in operation, with the solidlines indicating moving structure 3 in its upper position and the brokenlines the structure in its lower position.

The bearings for pivots 7 and 8 are rigidly secured to moving structure3.

The moving structure 3 in the embodiment in question slides back andforth in guiderails 9 and 9' rigidly secured to the wall 10 of thebasin.

Moving structure 3 is positioned or displaced by a rod 11 that can beactivated either manually or by means of a servomotor 12.

When moving structure 3 is raised, the cross-section of outlet 1increase to a prescribed extent and, when the structure is lowered, thecross-section is decreased to a prescribed extent. The shapes of outlet1 and of shutter 2 are designed in relation to each other to providedifferent outflow curves at various water levels.

An electric contact 20 may be mounted on one of the pivots, such aspivot 7 for example, and the pivoting angle can be displayed by thecontact.

An electric contact 21 may also be mounted on the shaft or rod 11, andthe position of the moving structure 3 can be displayed by this contact.

I claim:
 1. A flow control device for a sewage system, particularly arain basin, comprising: a sewage system with an outlet; at least oneshutter element mounted rotatably on a first pivot perpendicular to saidoutlet; a float arm mounted rotatably on a second pivot; transmissionmeans connecting said shutter element to said float arm, said outletbeing blocked to a predetermined extent by said shutter element whensaid float is at a maximum height, blockage of said outlet being reducedwhen said float is lower than said maximum height; a common movablemember carrying said first and second pivots, said first and secondpivots being displaced together with movement of said common member andbeing held on position by said common member at a selected maximum waterlevel; and guide means for guiding securely the movement of said commonmember, variation in position of said common member independent of saidfloat movement for varying flow characteristics steplessly from saidoutlet during normal operation of said control device by said shutterelement through a fixed relationship between said pivots and said commonmember, so that different outflow curves are obtained at different waterlevels sensed by said float.
 2. A flow control device as defined inclaim 1, wherein said common movable member is positioned manually.
 3. Aflow control device as defined in claim 1, including servomotor meansconnected to said common movable member through intermediate linkagemeans for positioning said common movable member.
 4. A flow controldevice as defined in claim 1, including electrical contact means mountedon one of said pivots for displaying pivoting angle.
 5. A flow controldevice as defined in claim 1, including linkage means connected to saidcommon movable member; and electrical contact means mounted on saidlinkage means for displaying position of said common movable member bysaid contact means.
 6. A flow control device as defined in claim 3,wherein said servomotor is remote-controlled.